GlasGrid Asphalt Pavement Reinforcement. October 21, 2016

Transcription

1 GlasGrid Asphalt Pavement Reinforcement October 21, 2016

2 Introduction to Cracks Crack sources are numerous and varied Cracks are consistent pavements aren t Solutions for cracks have had mixed results

3 Pavement Distress AC overlays deteriorate rapidly from: Load Associated Reflected Cracks ( ) Impulse Load PCC Pavement Joint Reflective Cracks, Fatigue/Alligator Cracks, Block Cracks, and Asphalt Construction Joint Cracks Displacement Associated Reflected Cracks ( ) - Continuous Thermal Cracks, Lane Widening Differential Settlement Cracks, and Shrinkage Cracks,

4 Transverse Cracking - Thermal Associated

5 Longitudinal Cracking - Thermal and Load Associated

6 Block Cracking - Load Associated

7 GlasGrid Solution: Increase the Tensile and Shear Characteristics of Asphaltic Concrete to overcome Crack Associated Stresses

8 ACC Pavement Reinforcement Required Qualities High Tensile with Low Elongation Glass has the necessary modulus advantage to reinforce Asphalt. Elastomeric polymer coating protects the glass as well as promotes ACC bonding to the ribs. Pressure sensitive adhesive ensures efficient installation. ACC reinforced by GlasGrid is millable, RAP is reusable.

9 Reinforcing Material Types High Stiffness vs. Low Stiffness The stiffness modulus of the GlasGrid is at least 10x that of the asphalt Fiberglass or Glass vs. Polyester 20 Load (lbf) Glass Polyester Extension (in)

10 The Products for our Solution Complete Road System TS : 100 kn/m x 100 kn/m Designed for Overlays Over : Fatigued Layers, Reflected Shrinkage Cracks, Block Cracks Uses Tensile Strength in two directions (Bi Directional)

11 The Products for our Solution Crack Detail Repair System TS : 200 kn/m x 100 kn/m Designed for Overlays Over : Reflected Joint Cracks, Thermal Cracks, or Construction Joints, eg. Lane Widening Joint Cracks Favors Tensile Strength in one direction, but still bidirectional

12 GlasGrid 8502 Placement Major Interstate

13 Overlay must be 11/2 min compacted Level course must be ¾ min compacted

14 GlasGrid Installation Requirements Critical Factors AC Wearing Course / Overlay Thickness 1.5 Leveling Course (i.e. Thermal Applications) Clean, Dry Surface AND Cured (Emulsion) Tack Seal Cracks >¼ Using Appropriate Sealant Factors Influencing Performance Achieving Optimum AC Density Use Appropriate PG Binder Grade (Thermal)

15 Product in Place

16 If local procedures or specifications require a tack coat to be used, it may be applied prior or after the installation of GlasGrid Sufficient time must be allowed for the tack to DRY & CURE

17 Applications

18 Applications : Roadways

19 Applications : Airports

20 Applications : Airport Aprons

21 Applications : Inter Urban Routes

22 Type 8501 Full Coverage - Youngstown,Ohio

23 Performance

24 GlasGrid over PCC Pavements LA DOTD LA 1 PCC slabs with good load transfer efficiency were rehabilitated with 3 of ACC. GlasGrid 8502 placed over PCC joints only in travel section, no GlasGrid in turn lanes After a little over one year cracks in turning lanes appeared, while travel section remains in good shape several years later.

25 This is what we want!

26 Long-Term Performance GlasGrid installed in 1997 in the driving lane of a major interstate highway. Passing lane is cracked where no reinforcement was used.

27 Long-term Performance GlasGrid installed in Nov Un-reinforced cracked pavement is only 5 months older than reinforced section.

28 Long Term Performance June ACC with GlasGrid July 2005

29 July ,000 yds² of GlasGrid 8511 placed Night work due to high daily traffic demand GlasGrid can be placed at 25,000 yd² /day Contractor s progress was dependent on Asphalt plant capacity not by GlasGrid laying efficiency.

30 Research

31 Laboratory Testing Texas A & M (Fatigue, Thermal Cracking) Dr. Robert Lytton - College Station, Texas, USA Delft University (Thermal Cracking Only) Dr Arian De Bondt, Ooms, Delft. Nottingham University, (Fatigue, Rutting, Reflective and Thermal Cracking) Saunders, Thom, Brown, Nottingham, UK NCAT National Center for Asphalt Technology, (full scale accelerated loading test track, Rutting) Ray Brown, Auburn, AL, USA

32 Texas A&M Laboratory Testing Flexural Test Results showed the following: Crack propagates to bottom of reinforcement and then is redirected horizontally

33 Existing pavement must be structurally sound If there is poor load transfer across the crack, no reinforcement will help as stated by Dr. Lytton at Texas A&M University Normal remedial work must be completed as for any standard overlay Seal all cracks wider than ¼

34 Texas A&M (Dr. Robert Lytton) studies conclude that: GlasGrid will extend the life of the overlay 2 to 3 times that of an unreinforced overlay A 3 overlay reinforced with GlasGrid, performs equivalent to 5-8 of unreinforced asphalt with regard to reflective cracking

35 NCAT Accelerated Loading Test Track Alburn, AL installed June Today Heavy duty structural design - built for the loading requirements that it was intended. Approx 24 of ACC over a significant granular base. Section W1, first section of the curve. NW Corner 4 of SMA PG binder GlasGrid 8501 in second half of the 200 ft length. 20 million ESAL s loading since installation. 100 ft longitudinal crack in the non GlasGrid section. GlasGrid section is without any visible cracking.

36 GlasGrid Section 2006 Non GlasGrid Section no cracks visible longitudinal cracking present

37 BENEFITS Increased service life of overlay Reduction in pavement maintenance frequency Reduction in pavement maintenance costs Minimize pavement closures to carry out maintenance GLASGRID ADDS VALUE TO YOUR PROJECT

38 QUESTIONS? GLASGRID PRESENTATION